Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d099d0b6436a930…

MALICIOUS

PDF

80.3 KB Created: 2021-04-02 04:17:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 15df3ac37a4172006ea7a7bef08a8be4 SHA-1: a5dbd20d47177724b48db689f7e45cf1c5c1d19b SHA-256: 4d099d0b6436a9301c862e6ea1d8d6cc41334c6458814993106a3864360d6f91
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link T1059.007 JavaScript

The PDF document contains a social engineering lure, presenting a fake error message about Windows update failures to trick the user into clicking a malicious link. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URL `https://zajinet.ru/strik?utm_term=pc+can%2527t+run+windows+10+couldn%2527t+update+the+system+reserved+partition` is likely the primary payload delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://zajinet.ru/strik?utm_term=pc+can%2527t+run+windows+10+couldn%2527t+update+the+system+reserved+partition PDF link annotation
    • http://berizala.22web.org/37660984159.pdfIn PDF document text
    • http://masajsalonunuz.com/enter_into_vs_enterhlsax.pdfIn PDF document text
    • http://idealicaitalia-ufficiale.site/fogsi_gdm_guidelinesq0393.pdfIn PDF document text
    • http://fikosigupim.22web.org/14173581395.pdfIn PDF document text
    • http://ita-yog.space/asperger_s_syndrome_survival_guide1w0mj.pdfIn PDF document text
    • http://lnstagramverifiedsbadgesforms.com/how_to_connect_bluetooth_to_clarion_m502301vy.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497353/normal_602473d98ddaa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393033/normal_5fd9c9ff7f22d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385009/normal_60533be6df918.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392661/normal_60591e8166dc5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://nutujetis.rf.gd/jegujetasuvixudimipak.pdfIn PDF document text
    • http://roxadib.epizy.com/erbauer_router_guide.pdfIn PDF document text
    • https://3d1db4d0-c196-4dd3-8d5c-bb108cafbd43.filesusr.com/ugd/479e38_3e0cfada9e2b4e559a591465e14c6403.pdf?index=trueIn PDF document text
    • https://bf23b77b-49a9-4bef-a898-a03cfb94aefa.filesusr.com/ugd/134172_94ec17e6e4324ffc8de12645bff8cde0.pdf?index=trueIn PDF document text
    • http://nupozefujelo.epizy.com/83126772074.pdfIn PDF document text
    • http://kuwosuz.rf.gd/numbers_1-_10_worksheets_writing.pdfIn PDF document text
    • https://034618a9-9b39-4f41-ad18-95bca1d1c80b.filesusr.com/ugd/48d9a1_0af03d091f734bd3aa649034959a2c1c.pdf?index=trueIn PDF document text
    • https://6f672a44-e16c-4921-a0f1-e3781c0647c5.filesusr.com/ugd/bda22a_f3e93454becd4209acd06dec9873b4ef.pdf?index=trueIn PDF document text
    • https://3ff4c494-4984-418a-b709-7a5c611cca0a.filesusr.com/ugd/adbee0_0d6a1a05c9294dffa0c5e19db5cc1ce5.pdf?index=trueIn PDF document text
    • http://kuxubofejudotif.rf.gd/biogeochemical_processes.pdfIn PDF document text
    • https://d6aab468-caab-4d9e-910f-d3bf64ae4104.filesusr.com/ugd/5438e3_c152555149a14ba0912efec3a948df4b.pdf?index=trueIn PDF document text
    • http://jorovupidad.rf.gd/48360219201.pdfIn PDF document text
    • http://nagasawovebuba.epizy.com/basic_civil_mechanical_engineering_notes.pdfIn PDF document text
    • https://5c90cfa9-af55-48e2-9430-1f3580382729.filesusr.com/ugd/e2b09b_6953d39879ec4d2ab382389054e02e74.pdf?index=trueIn PDF document text
    • http://sadamalaju.epizy.com/jaxiguvasanebiximijunatud.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f835.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF835 5796 bytes
SHA-256: 795a32000500e5ce2cc5b9bd5231d4c3907c3a6959768da8b5a1027eff4b3335
font_01_sfnt_off00010bed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BED 11320 bytes
SHA-256: 8e3c5fc03d3bc30f1d74164c748260bd091cef425d09a8a2031bebc2e0026aab

Open this report in the interactive analyzer, or submit your own file for analysis.